Switch



Oct. 12, 1937. v 5, R u BRlE 2,095,436

SWITCH Filed May 23, 1935 2 Sheets-Sheet 1 v n s a in w as 1 Q *1 3; I! ll 5 l3 hi n m u [m I T I I v I I F I W "5 lb W d0 4 -ll no w E '0 Q% 2 INVENTOR.

Oct. 12, 1937.

s. R. DU BRIE 2,095,436

SWITCH Filed May as, 1935 2 Sheets-Sheet 2 I N VE NTOR.

M v6, A6145 JWW ATTORNEY.

Patented Oct. 12, 1937 UNITED STATES PATENT OFFICE 2,095,426 SWITCH Stanley R. Du Brle, Detroit, Mich. Application May 23, 1935, Serial No. 22,974

4 Claims.

The switch disclosed in this application is of the pressure type and is characterized by its being made of stampings or the like.

For an understanding of the switch disclosed herein, the following specification should be read in connection with the appended drawings. In these drawings,

Figs. 1 and 2 are elevational views, with a. cover removed, of the switch in on and oil positions,

respectively;

Fig. 3 is a view as ii from the left of Fig. 1 with a binding post shield removed;

Fig. 4 is a view as if from the left of Fig. 2 with the shield in place;

Figs. 5, 6, 7, 8, and 9 are sections as it on lines 5-5, 6-6, 1- l, 8-4, and 9-4 01 Figs. 1, 1, 2, '7, and 5, respectively;

Fig. 7a is a view like Fig. 7 but showing a modiflcation.

20 Fig. 10 is a detailed view.

Referring to the drawings. it will be observed that the switch therein shown comprises a base plate ill and a casing ll. Under the base plate, which is circular in form, but which has an aper- 25 tured radially extending part i2 projecting therefrom, is a circular diaphragm ll of rubber or the like, and immediately under this diaphragm is a chambered diaphragm plate It. The base plate, the diaphragm, and the diaphragm plate are rel- 30 atively secured in assembly to provide a pressure chamber by means of the series of bolts it. Two of the bolts are passed through the base plate and lugs ll of the casing walls to secure the casing to the base plate, and thus to secure the casing and the pressure chamber in assembly.

Disposed within the pressure chamber and above the diaphragm is a pressure plate (not shown) provided with an upwardly extending pin 20 engaging the horizontal arm of the pressure 40 bell crank 22, the latter being pivotally mounted at 23. The vertical arm of the pressure crank is hooked over and has its upper end connected to the side wall of the casing by a coiled tension spring 28 and an adjusting bolt 26 threaded 45 through a nut 21. The last mentioned parts provide a well-known means for bodily shifting the diflerential or range of openings or closing pressure limits of the switch, and adjustment of these parts for shifting the range is accomplished 50 by movement 01 the nut 21 on the bolt 26.

The operating mechanism of the switch, as a whole, is connected to the pressure bell crank 22 through the horizontal arm 28 thereof, the latter having a hole 29 in which is the hooked upper 55 end 01. the snap action spring 3. whose lower end is secured to a threaded bolt or pin 32 which goes through a clear hole in the bight of-a throw arm 23 and threads through an adjusting nut II.

This construction provides an adjustment for increasing or decreasing the differential or oper- 5 ating range of the switch. I

The free ends of the throw arm are notched at II to receive the notched lugs 36 of an anchor plate I! welded to the casing II and thus form knife edge pivots for the throw arm. '10

A cross part II of the-throw arm rides between a tongue 39 01' a metal stamping riveted to an insulation contact carrying plate 40, and the stamping has bent-over tongues 4| disposed in slots 01 the anchor plate for pivotally suspending the plate 40.

The lower end of plate 40 is T-shaped and mounts stirrups 42 (Fig. 7) or is formed with seats 42a terminating in loops 42b (Fig. 7a) in which are double contact blades 43 whose contact tips ll engage contact tips on stationary contacts 45 riveted to a doubly flanged insulation plate 46 mounted on the side wall of the casing II and having line and load binding posts 41. The blades 43, bridging contacts 45, float in the stirrups or the loops and coiled springs 48 therein bias the blades against contacts 45; movement of blades 42 in the stirrups or loops 42 is guided by the blade notches 49 receiving sides of the stirrups or loops. 3

For limiting switch throw, throw arm 23 is formed with a lug 50 through whose tapped hole threads an adjustable screw 5| which engages a stop lug 52 welded to the casing II, and this lug has a tapped hole 53 receiving a screw which holds 5 a casing cover plate in place.

It will be observed that when the pressure bell crank 22 rocks clockwise on an increase in pressure, coil spring will move over center with a snap action and such movement will cause the throw arm 32 and the contact plate III to move for quick break, from the position shown. Conversely, a decrease in pressure will cause the switch to close, if it had been opened, the over center arrangement providing quick make movement for the parts.

It is also observed that the movement and mounting of the movable contacts are such that these engage the fixed contacts with a wiping action, so desirable in switch action. Further, instead of both points ll 01' a blade 43 making simultaneously, the upper ones make before the lower ones make; conversely, the lower contact points break before the upper contact points break.

crank with the bight of the throw arm, the ends of the throw arm being pivotally connected to.

fixed structure through knife edge bearings, a contact carrying arm pivotally mounted'on fixed structure, and having a slot in which rides a cross piece of the throw arm.

' 2; In a pressure switch mechanism, a pressure bell crank mounted to rock on its pivot with variations in the controlling pressure, a throw arm in the form of a U strap straddling an arm of the pressure bell'crank, an adjustably mounted coiled tension spring having its ends connected to and connecting the aforesaid arm of the pressure bell crank with the bight of the throw arm, the ends of I the throw arm'being pivotally connected to fixed structure through knife edge bearings, a contact carrying arm pivotally mounted on fixed structure, and having a slot in which ridesa cross piece of the throw arm, and a stop on the throw arm for engaging fixed structure to limit the movement of the throw arm.

3. In a pressure switch mechanism, a fixed' structure frame, a pressure bell crank pivotally mounted thereon to rock on its pivot with variations in the controlling pressure, a throw arm in theform of a U strap straddling an arm of the pressure bell crank, an adjustably mounted coiled tension spring having its ends connected to and connecting the aforesaid arm of the pressure bell crank with the bight of the throw arm, the ends of the throw arm being pivotally connected to the fixed structure frame through knife edge bearings, and a contact carrying arm pivotally mounted on the fixed structure frame, and operatively connected to the throw arm.

4. In pressure switch mechanism, a pressure bell crank mounted to rock 'on its pivot with variationsin the controlling pressure and having a horizontally extending portion, vertical arms pivotally mounted at their upper ends on fixed pivots near the extension and operatively connected to each other between their ends so as to swing witheach other in the same general direction, a coiled tension spring connecting the lower end of one arm with the extension, and contacts at the lower end of the other arm.

STANLEY R. DU BRIE. 

